The present invention relates a switch unit in which a switch controlling control knob is disposed within an opening in a switch cover in such a manner as to oscillate or rotate and a plated layer is provided on a surface of the switch cover.
For example, in a case where a switch unit is fabricated which is configured in such a manner that a see-saw type control knob 3 as is shown in FIG. 4 is provided within an opening 2 in a switch cover 1 as is shown in FIG. 2 in such a manner as to swing up and down, escape portions 4 need to be formed on a rear side of the switch cover 1 for permitting the control knob 3 to oscillate or swing up and down as required. Then, in a case where the switch cover 1 configured in the way described above is molded of a resin, as is shown in FIG. 3, a parting line 5 needs to be set in the vicinity of a rotational locus 3a (refer to FIG. 4) of the control knob 3 on a circumferential edge portion of the opening 2. The parting line 5 is a line that is to be formed between parting faces of two molds (although not shown, in this case, two upper and lower molds) in resin molding, and after molding, a so-called flash 6 is formed on the parting line 5 as a result of part of the resin protruding from between the parting faces. There may occur a situation in which an electro-plate layer 7 (refer to FIG. 4) is required to be provided on the surface of the switch cover 1 configured in the way described above through electroplating for the purpose of increasing the design properties thereof.
As this occurs, in the event that an electro-plate layer 7 is attempted to be provided on the surface of the switch cover 1 in such a state that the flash 6 so formed remains thereon, the electro-plate layer 7 (refer to a chain double-dashed line in FIG. 3) is eventually formed on the surface of the flash 6, as well. In case this actually happens, when the control knob 3 is operated, the control knob 3 strikes against the portion where the flash 6 is formed, leading to a fear that the electro-plate layer 7 is stripped off therefrom. In order to avoid this, although the flash 6 is made to be removed before the electro-plate layer 7 is so provided, to remove the flash 6, the flash removing work needs to be carried out separately. In addition, depending upon shapes of switch covers, there may be a situation in which the flash removing work is made difficult to be carried out.
Due to this, conventionally, the switch unit has been regarded as being difficult to be fabricated in which the control knob 3 is disposed within the opening 2 in the switch cover 1 on the surface of which the electro-plate layer 7 is to be provided in such a manner as to oscillate or rotate.
In addition, although this is not related directly to a problem that the invention is to solve, a technique of two-color molding in which a resin to which a plated layer can adhere and a resin to which a plated layer does not adhere are molded one on the other is disclosed, for example, in JP-A-2005-309103 or Patent Document 2.